Typically, oil well tubing has a build-up of paraffin or a like wax on the interior surface. Such buildup can interfere significantly in the flow of oil and other fluids within the tubing. It has been found useful to cause a rubber ball having an outer diameter slightly less than the internal diameter of the tubing to be driven by the oil or other fluid, such as water, through the pipelines, particularly between the well head and tank battery. The ball functions to in turn wipe the accumulated deposit of paraffin from the interior surface of the well tubing, pipeline or similar oil conduits.
U.S. Pat. No. 2,876,842 to Thomas W. McSpadden issued Mar. 10, 1959, and entitled "Method and Apparatus for Cleaning Wells," teaches the introduction of an oil soluble plug formed from a microcrystalline wax, such as a petroleum ceresin wax, of elongated cylindrical form sized slightly smaller than the diameter of an oil well tube at the well head, wiping an accumulated deposit of paraffin wax, scale or the like from the inside surface of the tubing.
The plug is introduced into the top of the well head tubing by removal of a bull plug, which is unscrewed from a cross attached to the well head and projecting upwardly of the same. The bull plug includes a perforated sleeve axially aligned with the tubing and having an internal diameter size thereto, which initially receives the plug.
U.S. Pat. Nos. 4,317,486 issued Mar. 2, 1982, to Monty E. Harris and entitled "Cementing Head Apparatus and Method of Operation," and 4,854,383 issued Aug. 8, 1989, to Ronald D. Arnold et al. and entitled "Manifold Arrangement for Use With a Top Drive Power Unit" teach the use of rotary ball valves having a diametrical cylindrical passage or bore through the center of the rotatable ball valve which is selectively aligned with the axis of the oil well tubing within which the valve structure is mounted for permitting the passage of a plug capable of being pushed by hydraulic pressure through the casing to clear the tubing, or rotated 90.degree. to the axis of the tubing to close off the fluid passage through the tubing and to prevent movement of the plug, which plug may be maintained within the portion of the tubing above the rotatable ball valve.
U.S. Pat. No. 3,035,640 issued May 22, 1962, to W. C. Gibson et al. and entitled "Kelly Cock" is directed to a cylindrical, rotary valve member within an enlarged casing portion of an oil pipeline in a oil well drilling apparatus for facilitating the insertion of a ball sized slightly smaller than the well tubing string, to seat the ball in the bore of a cement follower plug following the flow of cement downwardly into the string to shut off an opening therein and allowing pump pressure to move the cement follower plug down the casing until it seats into a float shoe. The body includes an axial flow chamber with an enlarged cylindrical portion carrying a transverse cylindrical bore whose axis intersects the axis of the through bore. Rotatably and sealably mounted within the transverse crossbar is a cylindrical plug having a diametrical flow passage therethrough at right angles through its axis having substantially the same diameter as the diameter of the through bore. Further, at one end of the plug, there is a reduced diameter axial bore which extends from that end to the diametrical flow passage which receives a threaded plug insert which is removable to permit the insertion of a ball which is permitted to fall downwardly within the axial bore of the enlarged casing and the axial bore of the pipeline string, upon 90.degree. rotation of the rotatable cylindrical plug from a position where it closes off the flow passage provided by the bore and the through bore of the enlarged casing to one where the diametric cylindrical flow passage within the rotatable cylindrical plug is aligned with that casing through bore.
U.S. Pat. No. 4,420,040 issued Dec. 13, 1983, to David P. Arbasak et al. and entitled "Ball Catcher" is directed to a ball catcher having a radially enlarged housing coupled to a casing of an oil well and functioning to catch a ball. A stinger, taking the form of an elongated annular cylindrical member whose sides are perforated, extends axially downwardly at the top of the radially enlarged casing, and stops the flow of balls moving upwardly with the liquid during well flow back operation after fracturing of the well formation. The balls are captured between the stinger and inwardly directed baffles fixed to the inner periphery of the radially enlarged casing at some distance below the lower end of the stinger.
While the apparatus of the various patents described above illustrate the use of balls or plugs or like elements which are fluid driven through a well tubing string, or similar piping, and elements for controlling the movement of such balls or plugs through the interior bore of the well tubing string, and for the introduction and catching of such balls, there is no simplified unitary valve structure capable of introduction of a paraffin cutting ball into a well tubing system, or capturing of such ball after travel a predetermined distance through the tubing for removing of the ball from the flow passage system, while ensuring that the paraffin removal ball does not harm the elements making up the string of casing or tubing and does not induce large hydraulic pressures within the elements of that apparatus, which permits the ball catcher to function as a valve for closing off the axial bore within the valve casing supporting the catcher, which readily permits bypass of the oil or other hydraulic fluid flowing through the interior of the tubing string, which permits the bypass passage itself to be closed off when needed to ensure the movement of a ball placed into the string through the string and which provides a ready arrangement for draining the valve cavity supporting the movable valve member having the dual function of closing off the string and the introduction of the paraffin removal ball, or removing of the same after catching of the ball during its movement through the tubing string from its point of insertion at some distance from the catcher.